May 5, 2009

Scientists Say Human Organs Could Be Harvested From Sheep

A Japanese scientist claims that humans may be able to harvest transplant organs from sheep within a decade.

Professor Yutaka Hanazono told London's Times Online that he his sheep has been successfully modified to develop a spare pancreas hidden in its underbelly.

Although the only viable donor for the spare pancreas would be a diabetic chimpanzee, Professor Hanazono said it represents an opportunity to provide harvestable human organs in sheep and ending the ethical debate over the use of human stem cells to create organs.

The pancreas currently growing inside the sheep was created using stem cells from monkeys, Hanazono said, but he believes that technology could one day be used to make sheep into living human organ banks.

Hanazono, who works at the Jichi Medical University, foresees a future where human livers, hearts, pancreases and skin can be grown in sheep. He says it could happen in the next decade, or two.

"We have made some very big advances here. There has historically been work on the potential of sheep as producers of human blood, but we are only slowly coming closer to the point where we can harvest sheep for human organs," Professor Hanazono told The Times.

"We have shown that in vivo (in a living animal) creation of organs is more efficient than making them in vitro (in a test tube) but now we really need to hurry."

Hanazono told The Times that Japanese law defines "death as the point when the heart permanently stops. The concept of brain death "” the phase at which organs can most effectively be harvested from donors "” does exist, but organs cannot be extracted at that point.

As a result, the organ donor system in Japan is virtually nonexistent, said Hanazono. In Japan the rate of organ donors per million people is less than 0.8, compared to about 27 in the US.

"To avert disaster, say doctors, Japan either needs the science of synthetic organ generation to advance faster than seems possible, or it needs a complete rethink on the Japanese definition of death," according to the Times.